Locking devices, such as high-security locks, fall into two broad categories: mechanical, and electro-mechanical. Typically, both types of locks are mounted on safes or other securable containers to protect valuables stored therein. These valuables include currency, jewelry, important paperwork and documents, firearms and ammunition, and other high valuable personal and commercial property and effects. These securable containers may be found in retail stores, homes, banking locations, and many other locations.
Both electro-mechanical locks and mechanical locks have some sort of input device (such as a keypad or rotating dial) that is mounted on an outside of the securable container. The lock is typically mounted on an inside of the securable container. Commonly, the lock has a bolt that prevents opening of the container by inhibiting movement of the container's boltworks when the container is secured. For example, the bolt may extend from a door or access panel of the container into a frame of the container, and prohibit movement of the door or access panel when the lock is in a secured state. When the lock is placed in the unsecure state, by providing an acceptable input to the lock via the input device, the bolt may retract into the lock body and thereby allow entry to the interior of the secured container by movement of the door or access panel. Arrangements of the lock, bolt, and access panel may vary depending on the needs of the individual or organization that requires a secured area; the number of bolts may also be any number greater than one.
Mechanical and electro-mechanical locks typically mount on the container utilizing mounting hole pattern and spindle hole pattern that is common to the lock manufacturer. Mechanical locks may have a spindle that mechanically connects a dial to the lock through a small hole, typically less than half an inch, in the container. The dial may be mounted on the outside of the container over the small hole with a spindle (typically constructed of a threaded rod) passing through the hole and attaching to the lock directly on the other side of the hole in the secure area of the container. A combination or secret code is entered by rotating the dial in a sequence to specific numbers marked on the dial. As the dial rotates, the spindle rotates, thus rotating wheels inside the mechanical lock. When the correct combination is entered, the wheels inside the lock align in a way to allow the lock bolt to be retracted. Alternatively, a key may be provided to a keyhole at the outside of the box, which may raise different pins within the lock so as to move each pin out of the way of a tumbler, which can then rotate and allow the lock bolt to be retracted. Mechanical locks typically do not include any electronic components or firmware, and therefore are non-programmable, except that a specific combination may be set by setting the position of the mechanical wheels.
Electro-mechanical locks typically have a numeric keypad on the outside of the container and a multi-conductor cable connecting the keypad to the lock inside the container. In some instances the multi-conductor cable may pass through the spindle hole. The multi-conductor cable transmits power and communications between the keypad and lock. Because of the small diameter spindle hole in the container, the number of conductors in the cable is limited; typically to 4 conductors. Some electro-mechanical locks may also have spindles, in addition to the multi-conductor cable, connecting the keypad to the lock.
The keypad transmits signals indicative of key presses to the lock and when a correct code is entered, the lock will either retract the bolt or permit the bolt to be retracted. Electro-mechanical locks typically use small motors to move or unblock the bolt, or small solenoids to unblock the bolt.